The answer to your question is "obviously yes, OpenACS can be
customized to do anything!" That said, it can't do it quite out of the
box. First of all, we don't have source code management
integration in v4 (and we only had very little stuff in v3 anyways).
The right platform for this is probably dotLRN, for scoping and
creation of developer communities and such. But you'll need to
develop reasonably large chunks of new functionality to match
SourceForge.
